Vermont Castings • Aspen C3 Owner’s Manual_R5 • 2019 - ___ • 11/19
12
8390-950c
D. Combustion Process
How the Aspen C3 Works:
Combustion control is achieved in the Aspen C3 through two
separate air delivery systems.
The Aspen C3 features Continuous Combustion Control™
(C3) technology, a heat activated technology that automatically
adjusts and delivers just the right amount of air to optimize
efficiency and heat output. In short, it keeps the fire in the
“sweet spot”. As the fuel burns, an automatic thermostat
reacts to the heat radiating from the stove and, consequently,
adjusts the air shutter attached to it.
As the fire intensity (and heat output) builds, the thermostat
slowly closes the air shutter, thereby restricting incoming
combustion air. As the fire intensity then wanes (and heat
output lessens), the thermostat responds and gradually
opens the air shutter which allows more combustion air to
again enliven the fire. This ebb and flow action functions
continuously to prolong the burn cycle until the fuel bed is
exhausted.
Another separate supply of oxygen is delivered to the upper
area of the firebox to support combustion of gases released
from the main fuel bed. This
Secondary Air
enters the stove
and is heated while passing through separate channels
before being delivered at the top of the firebox.
Burn Only High-Quality Wood
THE ASPEN C3 IS DESIGNED TO BURN NATURAL
WOOD ONLY; DO NOT BURN ANY OTHER FUELS.
You will enjoy the best results when burning wood that has
been adequately air-dried. Avoid burning “green” wood that
has not been properly seasoned. The wood should be no
longer than 18” (410 mm) in length, however, you will find
that thiner cuts ease refueling and promote the most efficient
combustion.
The best hardwood fuels include oak, maple, beech, ash,
and hickory that has been split, stacked, and air-dried outside
under cover for at least one year.
For areas that do not have a supply of hardwood, commonly
burned softwoods include tamarack, yellow pine, white pine,
Eastern red cedar, fir, and redwood. These too should be
properly dried.
Keep wood a safe distance from the heater and keep it out
of the areas around the heater used for refueling and ash
removal.
WARNING
!
OPERATE THIS STOVE ONLY WITH THE DOOR FULLY
CLOSED.
BURN SOLID WOOD FUEL ONLY, AND BURN IT
DIRECTLY ON THE GRATE. DO NOT ELEVATE THE
FUEL. DO NOT BURN COAL OR OTHER FUELS.
Cast iron is extremely strong, but it can be broken with a sharp
blow from a hammer or from the thermal shock of rapid and
extreme temperature change.
The cast plates expand and contract with changes in
temperature. When you first begin using your Aspen C3,
minimize thermal stress by allowing the plates to adjust
gradually during three or four initial break-in fires following
Steps.
1. Place several sheets of crumpled newspaper in the stove.
Avoid using glossy or colored paper, as these burn poorly.
At the front of the firebox, place on the paper six or eight
pieces of dry kindling split to a finger-width size, and on
the kindling lay two or three larger sticks of split dry wood
approximately 1-2” (25-51 mm) in diameter.
2. Light the newspaper and close the door. Gradually build
up the fire by adding a few 3-5” (80-120 mm) diameter
splits.
If this is one of the first few “break-in” fires, let
the fire burn brightly, and then let it die out.
• Some odor from the stove’s hot metal, the paint, and the
cement is normal for the first few fires.
NOTE:
Some chimneys need to be “primed,” or warmed up,
before they will draw sufficiently to sustain a fire. To correct
this situation, roll up a couple pieces of newspaper, place
them on top of the kindling and toward the back of the stove,
light them, and close the door. This should heat the chimney
enough to initiate strong draft.
Once the draft is established, open the front door and light
the rest of the fuel bed at the bottom. Do not light the main
bed of fuel until the chimney begins drawing.
Option 1:
Standard firestarting method above with all steps.
Option 2:
“Top-down" method to start a fire. Smoke emissions
when starting a fire can be difficult to control because the
stove is not yet heated to its optimum temperature. One
method of reducing emissions during a cold start-up is the
use of a "top-down" kindling procedure. In this, place larger
pieces of kindling on the bottom of the kindling pile followed
by smaller and smaller pieces as the pile is added to. Very
finely split pieces should be on the top.
E. Building & Maintaining a Fire
